For many applications employing polymeric materials, cross-linking of the polymer is a critical and necessary step in preparing many commercially viable products. Historically, one approach to cross-linking a polymer has been to introduce a reactive chemical component, commonly referred to as a “cross-linking agent.” Typical examples of cross-linking agents are melamines, formaldehyde, chromates, polyfunctional silanes, zirconates, borates, polyfunctional acids and polyfunctional amines.
More recently, polymers have been developed which do not require the addition of a cross-linking agent. Many of these polymers employ glycidyl or amine functionalities to enable the polymer to form covalent bonds to itself or other functional materials. This approach is advantageous because the product formulation is simple and the resultant product is a commercially viable polymeric material. For example, crosslinked polymers of N-vinyl amides, such as N-vinyl pyrrolidone (VP or HPVP) and N-vinyl caprolactam (VCL), can be made by the addition of a glycidyl methacrylate (GMA) functionality. See, B. S. R. Reddy et. al. in the Journal of Applied Polymer Science, Vol. 43, 251-258 (1991) and S. A. Sukhishvili et. al. in the Journal of Polymer Science: Part A: Polymer Chemistry, Vol. 44, 183-191 (2006).
Also, EP 0 103 184 assigned to Diamond Shamrock discloses hydrogel terpolymers of GMA (50%) and VP(40%) and hydroxyethylmethacrylate (HEMA) (10%). Finally, US 2007/0056900 assigned to BASF discloses polymers comprising 60-99% by weight of a least one N-vinyl amide (e.g., VP, VCL) and 1-40% by weight of at least one monomer selected from, for example, GMA, HEMA, aminostyrene compounds, and imidazoles.
Given the many uses for cross-linked polymeric materials, there is a constant need for a next generation cross-linkable polymers. The present invention is directed to polymers containing polymerizable functionalities.